Circuit board and optical module

Abstract

The embodiment of the utility model discloses a circuit board and an optical module, the circuit board has a first direction, a second direction and a third direction which are perpendicular in pairs, the first direction and the second direction are parallel to the surface of the circuit board, the third direction is perpendicular to the surface of the circuit board, the circuit board is composed of a plurality of layer structures stacked in the third direction, and the first direction is perpendicular to the second direction. In the first direction, the circuit board comprises a first area and a second area, and the size of the first area in the second direction is smaller than that of the second area in the second direction; at least one layer structure of the circuit board is provided with at least one reinforcing structure, and the reinforcing structure continuously extends in the first area and penetrates through the two ends, in the first direction, of the first area. The structural strength of the narrow area of the circuit board is improved, the problems that the structural strength of the narrow area of the circuit board is weakened and the narrow area is easy to bend or break due to local hollowing of the circuit board are solved, the surface space of the circuit board is not occupied, and the influence on the layout of the circuit board is small.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of circuit boards, and in particular to a circuit board and an optical module. BACKGROUND

[0002] A PCB (Printed Circuit Board) is a basic component used to support and connect electronic components, and its main function is to provide physical support and circuit connection for electronic components. The PCB is a multi-layer structure, including alternating layers of dielectric layers and conductive layers. The dielectric layer is usually made of resin and glass fiber. The resin has insulating properties and can provide physical support for the PCB and act as an insulating layer for the conductive layer. The glass fiber is in the form of fine fibers in the resin, which increases the mechanical strength and thermal performance of the PCB. The conductive layer is usually made of conductive material for wiring and connecting electronic components on the PCB. The multi-layer structure of the PCB can be designed and manufactured according to the requirements of the multi-layer stacked structure, such as 4 layers, 6 layers, 8 layers, etc.

[0003] In practical applications, in order to improve the high-frequency performance of the signal and the heat dissipation performance of the product, etc., a hollow area is usually opened on the PCB as a mounting groove, and a heat sink and a chip are arranged in the mounting groove of the PCB. In some lightweight design applications, such as aerospace, a large area of the PCB can be hollowed out to form a large area of holes on the PCB to reduce the weight of the entire circuit board.

[0004] However, opening slots or holes on the PCB can weaken the structural strength and stability of the PCB, making the PCB more prone to bending or even breaking during transportation, operation, and subsequent assembly of the application product, which can also affect the long-term service life of the PCB. Invention content

[0005] Embodiments of the present application provide a circuit board and an optical module to improve the mechanical strength of the circuit board.

[0006] In a first aspect, a circuit board is provided, the circuit board having a first direction, a second direction and a third direction perpendicular to each other, the first direction and the second direction being parallel to the surface of the circuit board, the third direction being perpendicular to the surface of the circuit board, the circuit board being composed of a plurality of layer structures stacked along the third direction;

[0007] In the first direction, the circuit board includes a first region and a second region, the size of the first region in the second direction being smaller than the size of the second region in the second direction;

[0008] Wherein, at least one of the layer structures of the circuit board has at least one reinforcing structure, and the reinforcing structure extends continuously in the first region and passes through both ends of the first region along the first direction.

[0009] Optionally, the reinforcing structure is present in at least two of the layer structures of the circuit board, and the reinforcing structures located in different layer structures are aligned or staggered along the third direction;

[0010] And / or, at least one of the layer structures of the circuit board has a plurality of the reinforcing structures.

[0011] Optionally, the layer structure includes stacked conductive layers and dielectric layers, and at least one of the layer structures of the circuit board has a plurality of the reinforcing structures, wherein the plurality of the reinforcing structures in the at least one layer structure are interconnected through the conductive layers.

[0012] Optionally, the reinforcing structure is provided in each of the multiple consecutively stacked layer structures, wherein,

[0013] The two reinforcing structures located on adjacent layers and aligned with each other are stacked and connected as a whole;

[0014] And / or, two reinforcing structures located in adjacent layers and staggered from each other are connected by a conductive layer located between the two adjacent layer structures.

[0015] Optionally, multiple reinforcing structures in the multiple layer structures together form a structure with a "U" or "H" shaped cross-section, wherein the cross-section is the section of the circuit board perpendicular to the first direction.

[0016] Optionally, the reinforcing structure is an electroplating filler tank that penetrates the dielectric layer or the layer structure in a third direction.

[0017] Optionally, the size of the reinforcing structure in the second direction is ∈ [60um, 100um].

[0018] Optionally, the first region is provided with a power line, the power line including at least one of the reinforcing structures, and / or the first region is provided with a grounding wire, the grounding wire including at least one of the reinforcing structures; the reinforcing structures located on the power line are mutually insulated from the reinforcing structures located on the grounding wire.

[0019] Optionally, the circuit board further includes a cutout area, wherein in the second direction, the first area is a narrow arm located on one or both sides of the cutout area.

[0020] Optionally, in the second direction, the size of the narrow arm is greater than or equal to 2.5 mm.

[0021] In a second aspect, the optical module is provided, characterized in that comprising: an optical assembly and the circuit board as described in any of the above, the optical assembly is located at the edge of the circuit board and is electrically connected with the edge of the first area or the edge of the second area.

[0022] The beneficial effects of the present application: by arranging the reinforcing structure in at least one layer structure of the circuit board, the reinforcing structure continuously extends in the first area of the circuit board and penetrates through both ends of the first area, thereby improving the structural strength of the first area, solving the problem that the structural strength of the narrow area of the circuit board is weakened due to local hollowing, and the circuit board is easy to be bent or broken, and the reinforcing structure does not occupy the surface space of the circuit board, and has less influence on the layout of the circuit board. BRIEF DESCRIPTION OF DRAWINGS

[0023] The technical solutions and other beneficial effects of the present application will be apparent from the following detailed description of the specific embodiments of the present application, combined with the accompanying drawings.

[0024] Figure 1 is a structural schematic diagram of the circuit board provided by an embodiment of the present application;

[0025] Figure 2 is a structural schematic diagram of the circuit board provided by an embodiment of the present application; Figure 1 is a schematic diagram of the cross section at A-A;

[0026] Figure 3 is a structural schematic diagram of the circuit board provided by an embodiment of the present application; Figure 1 is a schematic diagram of the cross section at B-B;

[0027] Figure 4 is a structural schematic diagram of the circuit board provided by an embodiment of the present application; Figure 1 is a schematic diagram of the cross section at A-A;

[0028] Figure 5 is a structural schematic diagram of the circuit board provided by an embodiment of the present application; Figure 1 is a schematic diagram of the cross section at A-A;

[0029] Figure 6 is a structural schematic diagram of the optical module provided by an embodiment of the present application.

[0030] Explanation of reference signs:

[0031] 10, layer structure; 11, dielectric layer; 12, conductive layer;

[0032] 20, first area; 21, second area;

[0033] 30, reinforcing structure;

[0034] 40, narrow arm;

[0035] 50, hollowed area;

[0036] 60, optical component; 61, heat sink; 62, optoelectronic chip. DETAILED DESCRIPTION

[0037] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described in the specification are only intended to interpret the present application, and are not intended to limit the present application.

[0038] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like are based on the orientation or positional relationship shown in the drawings, and are only intended to facilitate the description of the present application and simplify the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0039] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be a fixed connection, or a detachable connection, or an integral connection; it can be a mechanical connection, it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0040] In the present application, unless otherwise explicitly specified and limited, the "upper" or "lower" of the first feature to the second feature can include the direct contact of the first and second features, or can include the contact of the first and second features through another feature between them. Moreover, the "upper", "upper" and "upper" of the first feature to the second feature include the vertical direction of the first feature above and obliquely above the second feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The "below", "below" and "below" of the first feature to the second feature include the vertical direction of the first feature above and obliquely above the second feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0041] The embodiments of the present application disclose a circuit board, referring to Figure 1 、 Figure 2 and Figure 3 , the circuit board has a first direction, a second direction and a third direction which are perpendicular to each other, wherein the first direction and the second direction are parallel to the surface of the circuit board, and the third direction is perpendicular to the surface of the circuit board. Further, the circuit board is composed of a plurality of layer structures 10 which are stacked along the third direction, and along the first direction, the circuit board includes a first region 20 and a second region 21, and the size of the first region 20 in the second direction is smaller than the size of the second region 21 in the second direction. The layer structure 10 includes a conductive layer 12 and a dielectric layer 11 which are stacked, wherein the dielectric layer 11 is made of insulating material, such as resin and the like.

[0042] Compared with the second region 21, the first region 20 has a narrower width, a poor structural strength, a weaker bending resistance and impact resistance, and is most likely to be bent or even broken during transportation or subsequent mounting of other elements or components.

[0043] In the embodiments of the present application, referring to Figure 3 , at least one reinforcing structure 30 is arranged in at least one layer structure 10 of the circuit board, and the reinforcing structure 30 continuously extends in the first region 20 and penetrates both ends of the first region 20 along the first direction. That is, the first region 20 has a continuous reinforcing structure 30 along the long and narrow direction thereof (in the embodiments disclosed in the present application, the long and narrow direction can refer to the first direction in Figure 1 ). In this way, the reinforcing structure 30 can act as a “bridge” to effectively transmit external force from one end to the other end, so that the external force is not concentrated in a small range of the first region 20, but is distributed along the entire reinforcing structure 30, thereby avoiding local excessive stress. Especially in the case of bending, the reinforcing structure 30 can prevent local bending and balance external force. Thus, the structural strength of the first region 20 is improved, the problem that the structural strength of the narrow region of the circuit board is weakened due to local hollowing and the narrow region is easily bent or broken is solved, and the reinforcing structure 30 does not occupy the surface space of the circuit board and has little influence on the layout of the circuit board. The reinforcing structure 30 is an electroplated filling slot which penetrates the dielectric layer 11 or the layer structure 10 in the third direction.

[0044] Specifically, in some embodiments, the circuit board further includes a hollow region 50, and the first region 20 is located on the narrow arm 40 on one side or both sides of the hollow region 50 in the second direction. As Figure 1In the embodiment shown, the hollowed region 50 has a narrow arm 40 on each side in the second direction. In other embodiments, the hollowed region can have a narrow arm 40 on only one side, for example, when the hollowed region is a notch on one side of the circuit board, the other side of the notch forms a single narrow arm 40. It should be noted that the projection of the hollowed region 50 in the third direction is irregular or polygonal, therefore, the narrow arms 40 on each side of the hollowed region 50 can be straight narrow arms 40 or irregular narrow arms 40, and the dimensions of the narrow arms 40 on each side of the hollowed region 50 in the first direction can be the same or different. In the second direction, the dimension of the single narrow arm 40 is greater than or equal to 2.5 mm, in other words, the dimension of the first region 20 in the second direction is greater than or equal to 2.5 mm to meet the basic strength requirement. Further, in some embodiments, the dimension of the reinforcing structure 30 in the first direction is greater than or equal to the dimension of the narrow arm 40 in the first direction. When the dimension of the reinforcing structure 30 in the first direction is greater than the dimension of the narrow arm 40 in the first direction, the reinforcing structure 30 extends onto the second region 21. That is, the reinforcing structure 30 is arranged at the junction of the first region 20 and the second region 21 to enhance the structural strength of the junction.

[0045] With reference to Figure 2 When the reinforcing structure 30 is arranged in each of the plurality of layer structures 10 of the circuit board, the reinforcing structures 30 in different layer structures 10 can be arranged in alignment or staggered in the third direction. In Figure 2 In the embodiment shown, there are two reinforcing structures 30 in one layer structure 10. In some embodiments, a plurality of reinforcing structures 30 can be arranged in each of the plurality of layer structures 10, or only one reinforcing structure 30 can be arranged in each of the plurality of layer structures 10. When the reinforcing structures 30 in adjacent layer structures 10 are arranged in alignment in the third direction, the rigidity and bending resistance of the adjacent two layer structures 10 can be effectively increased. The aligned reinforcing structures 30 are similar to a continuous support through the plurality of layer structures 10, so that external force can be directly transmitted from the upper layer to the lower layer, thereby forming an integrated load-bearing system in the adjacent two layer structures 10. When the reinforcing structures 30 in different layer structures 10 are arranged in staggered, the stress in different directions can be better dispersed, and the fatigue resistance of the circuit board is improved, thereby prolonging the service life of the circuit board. In this embodiment, the reinforcing structures 30 in different layers are partially aligned and partially staggered, and in other embodiments, the reinforcing structures 30 can be all aligned or all staggered.

[0046] With reference to Figure 2, in this embodiment, through-holes can be formed in the corresponding layer structure 10 to penetrate its dielectric layer 11 or penetrate its conductive layer 12 and dielectric layer 11, and then electroplated filling grooves are formed in the through-holes by electroplating and filling conductive metal. After the conductive metal is filled in the through-holes, it is connected to the conductive layer 12 in the same layer structure 10 or an adjacent layer structure 10. In this embodiment, the dimension of the strengthening structure 30 in the second direction ∈[60um, 100um], that is, the width of the cross-section of the strengthening structure 30 ranges from [60um, 100um], which can effectively increase the structural strength and minimize the impact on the structure of the first region 20. In addition, the through-hole penetrates the dielectric layer 11 or the layer structure 10, and the structure of the electroplated filling groove is the strengthening structure 30 of the corresponding layer structure 10. Therefore, the dimension of the strengthening structure 30 in the third direction is equal to the dimension of the dielectric layer 11 or the layer structure 10 in the third direction. That is to say, the thickness of the strengthening structure 30 in a single layer structure 10 is the same as the thickness of the dielectric layer 11 or the layer structure 10. Please refer to Figure 4 In the embodiment shown, multiple strengthening structures 30 are provided in at least one layer structure 10 of the circuit board, and the multiple strengthening structures 30 in at least one layer structure 10 are interconnected through the conductive layer 12. The multiple strengthening structures 30 are interconnected through the conductive layer 12 to form a more stable strengthening combination, which can further improve the structural strength of the circuit board.

[0047] In addition, in this embodiment, strengthening structures 30 are provided in multiple continuously stacked layer structures 10 of the circuit board. Among them, two strengthening structures 30 located in adjacent layers and aligned with each other are stacked and connected into one body; two strengthening structures 30 located in adjacent layers and offset from each other are connected through the conductive layer 12 located between the two adjacent layer structures 10. In this way, through the interconnection of multiple strengthening structures 30 in the second and third directions, a strengthening combination structure similar to a frame is formed, which can effectively resist the bending of the circuit board in the third direction, and at the same time can provide additional support and stability, preventing the circuit board from being damaged or broken due to bending, thereby effectively improving the structural strength and structural stability of the circuit board.

[0048] Specifically, please refer to Figure 4 In the embodiment shown, it includes multiple strengthening structures 30 stacked and connected into one body in the third direction, and multiple strengthening structures 30 offset in the third direction but connected through the conductive layer 12, and two strengthening structures 30 in one layer structure 10 are connected through the conductive layer 12. In this way, the multiple strengthening structures 30 in this embodiment together form a structure with a cross-section approximately in the shape of an "H", which has stronger stability and better strengthening effect. It should be noted that the above cross-section is the cross-section of the circuit board perpendicular to the first direction. In some embodiments, multiple "H"-shaped parallel structures or structures similar to the shape of "卅" can also be constructed through multiple strengthening structures 30 to further improve the structural strength of the circuit board.

[0049] Please refer to Figure 5 the illustrated embodiments, which are similar to those of Figure 4 In these embodiments, multiple reinforcing structures 30 are also interconnected in the second and third directions to achieve a better reinforcing effect. The difference is that in this embodiment, in the two layer structures 10, the respective two reinforcing structures 30 are connected by a conductive layer 12, and together with the multiple reinforcing structures 30 stacked or interconnected in the third direction, they form a combined structure with a cross-section approximately in the shape of a "square". In some embodiments, a structure with multiple "squares" connected in parallel can also be constructed by multiple reinforcing structures 30 to form structures similar to a "day" shape or a "field" shape, etc., to further improve the structural strength of the circuit board.

[0050] In some embodiments, a power line and a ground line are also provided in the first region 20 of the circuit board to transmit power between the first region 20 and the second region 21, or to provide a reference ground in the first region 20, etc. At this time, the reinforcing structure 30 can be part of the power line or part of the ground line. That is, the power line can include at least one reinforcing structure 30, or the ground line includes at least one reinforcing structure 30. It should be noted that the reinforcing structure 30 acting as the power line and the reinforcing structure 30 acting as the ground line are insulated from each other. In this way, the reinforcing structure 30 is used as both the power line or the ground line of the circuit board, without affecting the wiring of the circuit board, and at the same time improves the structural strength of the circuit board, solving the problem that the structural strength of the relatively narrow area of the circuit board is weakened due to local hollowing, and it is easy to be bent or broken.

[0051] The embodiment of the present application also discloses an optical module, which includes an optical component 60 and the above-mentioned disclosed circuit board. The optical component 60 is located at the edge of the circuit board and is electrically connected to the edge of the first region 20 or the edge of the second region 21.

[0052] Specifically, please refer to Figure 6 . In this embodiment, the optical component 60 includes a heat sink 61 and a photoelectric chip 62 located on the heat sink 61. Multiple photoelectric chips 62 can be provided, which can be laser chips, photodetector chips, photon integration chips, or a combination thereof. The circuit board has a hollowed-out area, and the first region 20 is the narrow arms 40 located on both sides of the hollowed-out area. The body of the heat sink 61 is located in the hollowed-out area and is lapped with the circuit board. The photoelectric chip 62 is also located in the hollowed-out area, placed on the heat sink 61, and is arranged at a position adjacent to the edge of the second region 21 of the circuit board. The optical component 60 is electrically connected to the circuit board through bonding wires.

[0053] Any technical features in the above embodiments can be combined, and for the sake of brevity, not all possible combinations are described above, however, as long as the combinations do not conflict with each other, they should be considered to be within the scope of the present disclosure.

[0054] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the application. It should be pointed out that for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A wiring board, characterized by, The circuit board has a first direction, a second direction, and a third direction that are perpendicular to each other. The first direction and the second direction are both parallel to the surface of the circuit board, and the third direction is perpendicular to the surface of the circuit board. The circuit board is composed of multiple layers stacked along the third direction. Along the first direction, the circuit board includes a first region and a second region, wherein the size of the first region in the second direction is smaller than the size of the second region in the second direction; Wherein, at least one of the layer structures of the circuit board has at least one reinforcing structure, and the reinforcing structure extends continuously in the first region and passes through both ends of the first region along the first direction.

2. The circuit board according to claim 1, characterized by The reinforcing structure is present in at least two of the layer structures of the circuit board, and the reinforcing structures located in different layer structures are aligned or staggered along the third direction. And / or, at least one of the layer structures of the circuit board has a plurality of the reinforcing structures.

3. The circuit board according to claim 1, wherein The layer structure includes stacked conductive layers and dielectric layers, and at least one of the layer structures of the circuit board has a plurality of the reinforcing structures, wherein the plurality of the reinforcing structures in the at least one layer structure are interconnected through the conductive layers.

4. The circuit board according to claim 3, wherein The reinforcing structure is provided in each of the multiple consecutively stacked layer structures, wherein, The two reinforcing structures located on adjacent layers and aligned with each other are stacked and connected as a whole; And / or, two reinforcing structures located in adjacent layers and staggered from each other are connected by a conductive layer located between the two adjacent layer structures.

5. The circuit board according to claim 4, wherein The multiple reinforcing structures in the multiple layer structures together form a structure with a "U" or "H" shaped cross-section, wherein the cross-section is the section of the circuit board perpendicular to the first direction.

6. The circuit board according to claim 3, wherein The reinforcing structure is an electroplating filling tank that penetrates the dielectric layer or the layer structure in a third direction.

7. The circuit board according to claim 3, wherein The size of the reinforcing structure in the second direction is [60um, 100um].

8. The circuit board of claim 6, wherein The first area is provided with a power line, the power line including at least one of the aforementioned reinforcing structures, and / or the first area is provided with a grounding wire, the grounding wire including at least one of the aforementioned reinforcing structures; The reinforcing structure located on the power line is insulated from the reinforcing structure located on the grounding wire.

9. The circuit board according to claim 1, wherein The circuit board also includes a cutout area, and in the second direction, the first area is a narrow arm located on one or both sides of the cutout area.

10. The circuit board according to claim 9, wherein In the second direction, the size of the narrow arm is greater than or equal to 2.5 mm.

11. An optical module characterized by comprising: include: The optical component and the circuit board as described in any one of claims 1-10, wherein the optical component is located at the edge of the circuit board and is electrically connected to the edge of the first region or the edge of the second region.

Images